Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already cover read-only, idempotent, non-destructive, closed-world behavior, so the description's added value is the auth requirement (pwk_live_ key with a URL to obtain it) and a precise failure contract including retry_recommended and retry_after_seconds, which tells the agent how to recover from errors. It stops short of describing the success payload, but that is covered by the output schema.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three short sentences, front-loaded with the core action, then auth, then error behavior. Every sentence carries actionable information; nothing is padding.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a two-required-parameter read tool with full schema coverage, annotations, and an output schema, the description covers the remaining burdens: authentication setup and the error/retry contract. Nothing an agent needs to call it correctly is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% and alert_id's schema description already points to create_price_alert/list_price_alerts, so baseline is 3. The description adds one genuine thing the schema does not: where to acquire the api_key (the profile#api-keys URL), which directly helps the agent satisfy a required parameter.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource with explicit cardinality: 'Get one price alert by alert_id'. The singular-scope phrasing separates it from list_price_alerts and search-style siblings without requiring the agent to open either schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The 'by alert_id' phrasing implies when this tool is appropriate versus the listing sibling, and the API key provenance gives practical setup context. However, it never states prerequisites, exclusions, or names an alternative explicitly ('use list_price_alerts to enumerate'), leaving selection to inference.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.